[Bug middle-end/52996] [4.8 Regression] ice in verify_loop_structure, at cfgloop.c:1567

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=52996

--- Comment #2 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-04-16 10:58:06 UTC ---
Looks like a pre-existing bug to me - when we unswitch loops computing
irreducible regions before / after that can lead to inconsistent results.

Loop preserving leads to different loop structure at the beginning of
RTL unswitching compared to the 4.7 branch.